Hi, Robin
You can get your Grandfather's will copy from the Sub-Registrar's office. You should apply just an application with non judicial stamp aprox Rs. 2.00 in which you have to mention your Grandfather's name, address and if possible the will copy no., date of will. then give it in the office of Sub Registrar. You also have to pay some deposit amout i.e. cost of copy with the application to Sub-Registrar.
After a week if Sub-Registrar will fail to provide a copy of your grandfather's will to you, You would go through
RTI.
In which area your Grandfather was belong to, that Sub-Registrar has jurisdiction. Please conform in the office of Sub-Registrar that such particular area has been under which sub registrar ? and then procide with above mention procidure......
Regards.